In the fabrication of electronic devices, optical components, storage components, bioelectronic components and the like, not only higher performance and further miniaturization are demanded, but also a reduction of the manufacture cost is required at the same time. Under the circumstances, the imprint lithography is highlighted since it can reduce the cost of micropatterning as compared with the conventional lithography processes. In the imprint lithography, a (topographic) pattern of protrusions and recessions is formed by mechanical means. Specifically a mold-forming substrate having a desired topographic pattern on the surface is pressed to a resin layer of given thickness on a recipient substrate for thereby transferring the topographic pattern on the mold to the resin layer. See Patent Document 1. Substrates used in the imprint lithography have different outer shapes including rectangular shape of 65 mm squares or 152 mm squares, and circular shape having a diameter of 50 mm, 100 mm, 150 mm or 200 mm, with a choice being made in accordance with the intended application.
In the imprint lithography, the resin layer to which the topographic pattern has been transferred by pressing is cured whereby the shape of the resin layer is retained. The cure may be implemented typically by UV cure and heat cure modes. In either mode, it is important to press the mold-forming substrate and the resin layer-bearing recipient substrate together while maintaining parallelism between them and providing a uniform pressure within the contact plane. The mold-forming substrate to be provided with a topographic pattern is required to have a high shape accuracy. See Patent Document 2.
In recent years, the photo (UV) nanoimprint lithography encounters an increasing demand to provide a mold-forming substrate with a finer size pattern or more complex pattern for transfer. In such high-definition imprint lithography, very precise positioning at high accuracy, control of compression pressure, and control of pattern shape are required. Under the circumstances, in the imprint lithography using rectangular substrates, the rectangular substrates themselves must have a high shape accuracy.
For example, Patent Document 3 discloses an actuation system comprising a plurality of actuators disposed so as to enclose a rectangular substrate, wherein the end surfaces of the substrate are compressed by a plurality of forces, for thereby bowing or deforming the compressed portion of the substrate, for thereby accomplishing compression and pattern shape control at a high accuracy.